如何讓Apache CLI處理雙連擊？

Question

我已經看過文檔，但看不到如何讓Apache Commons CLI處理通常會終止選項處理的雙連字符「選項」。

考慮以下命令行，其具有「-opt」選項，可以採取未指定的可選參數：我要的選項與在這種情況下，沒有爭論最終

MyProgram -opt -- param1 param2 

，但是Apache返回「 - 」作爲參數。如果該選項允許多於一個參數，則某些或全部參數將作爲參數返回。

這裏是說明問題的示例代碼：

package com.lifetouch.commons.cli; 

import java.util.Arrays; 
import org.apache.commons.cli.*; 

public class DoubleHyphen { 
    private static Options options = new Options(); 

    public static void main(String args[]) { 
    // One required option with an optional argument: 
    @SuppressWarnings("static-access") 
    OptionBuilder builder = OptionBuilder.isRequired(true). 
      withDescription("one optional arg"). 
      withArgName("optArg").hasOptionalArgs(1); 
    options.addOption(builder.create("opt")); 

    // Illustrate the issue: 
    doCliTest(new String[] { "-opt"}); 
    doCliTest(new String[] { "-opt", "optArg", "param"}); 
    doCliTest(new String[] { "-opt", "--", "param"}); 
    // What I want is for the double-dash to terminate option processing. 
    // Note that if "opt" used hasOptionalArgs(2) then "param" would be a second 
    // argument to that option (rather than an application parameter). 
    } 

    private static void doCliTest(String[] args) { 
    System.out.println("\nTEST CASE -- command line items: " + Arrays.toString(args)); 

    // Parse the command line: 
    CommandLine cmdline = null; 
    try { 
     CommandLineParser parser = new GnuParser(); 
     cmdline = parser.parse(options, args); // using stopAtNonOption does not help 
    } catch (ParseException ex) { 
     System.err.println("Command line parse error: " + ex); 
     return; 
    } 

    // Observe the results for the option and argument: 
    String optArgs[] = cmdline.getOptionValues("opt"); 
    if (null == optArgs) { 
     System.out.println("No args specified for opt"); 
    } else { 
     System.out.println(optArgs.length + " arg(s) for -opt option: " + 
       Arrays.toString(optArgs)); 
    } 

    // Observe the results for the command-line parameters: 
    String tmp = Arrays.toString(cmdline.getArgList().toArray()); 
    System.out.println(cmdline.getArgList().size() + 
      " command-line parameter(s): " + tmp); 
    } 
} 

Answer 1

爲了處理特殊標記--作爲一個選項終止，則必須使用POSIX解析器。

使用

CommandLineParser parser = new PosixParser(); 

，而不是

CommandLineParser parser = new GnuParser();